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PSoC 4 MCU

MrMa_286121
New Contributor II

Hi!

   

I was wondering whether is it possible to connect (VSSA and VDDA) to a different supply voltage other than that is being used for (VSSD and VDDD).

   

Also is it possible to connect VSSA to a slightly negative voltage, say -200mV as compared to VSSD which is referenced 0V for digital peripherals.

   

The configuration would look like:

   

VDDD = 3.3V

   

VSSD = 0V

   

VSSA = -0.2V

   

VDDA = 3.1V  (VDDA-VSSA = 3.3V)

   

Thanks

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1 Solution
JoMe_264151
Expert II

Won't work. Vdda must be the highest voltage for the chip.

   

 

   

Bob

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3 Replies
JoMe_264151
Expert II

Won't work. Vdda must be the highest voltage for the chip.

   

 

   

Bob

View solution in original post

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MrMa_286121
New Contributor II

Well in that case how about this:

   

VDDD = 3.3V

   

VSSD = 0V

   

VSSA = -0.2V

   

VDDA = 4.8V  (VDDA-VSSA = 5VV)

   

 

   

Are the VDDD and VDDA pins connected internally? (Same for VSSD and VSSA)

   

Also, if the requirement that VDDA must be >= VDDD is fullfilled, then is it OK to have VSSA biased to a slightly negative voltage?

   

This is to take care of saturation of analog peripherals and also to implement differential measurement for voltages that may swing to negative values.

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JoMe_264151
Expert II

That is below the "Absolute Maximum Ratings". You'll need to test for yourself if it has the wanted effect or just a defect 😉

   

 

   

Bob

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